1. Field of the Invention
The present invention relates to a device for providing solution such as a colored resin composition for a color filter, a black resin composition, a transparent resin composition, a developing fluid such as a resist material or the like, a cleaning fluid, an etching fluid and a removing fluid or the like.
2. Description of the Related Art
A coloring sensitive matter for a color filter to be used for a color display is served with being bottled in units of, for example, 10 kg and it is provided to an applying device in a pressure tank system. The pressure tank system is a system such that a bottle containing a coloring sensitive matter is arranged in a tank and the pressurized air is supplied in this tank so that the coloring sensitive matter is discharged to the exterior of the tank by its pressure.
In order to ceaselessly provide a coloring sensitive matter to the applying device, conventionally, two tanks are arranged with respect to one applying device and the tanks are used with being switched in response to the consumption ratio of the coloring sensitive matter in each tank. A remaining amount of the coloring sensitive matter in each tank is specified by detecting a weight of the tank with a weight sensor. If the weight of the tank, which has been used, is lower than a predetermined lower limit value, another tank is selected, since it is assumed that the remaining amount of the coloring sensitive matter in the tank falls short.
In the above described process for applying a coloring sensitive matter for a color filter, even if a very small air bubble mixes in, it is determined that the application fails. For example, even if only one air bubble (i.e., a micro bubble) with a diameter of about 30 μm mixes in a surface of a substrate with a size in a diagonal direction exceeds 1,000 m, it is determined that the application fails. Therefore, conventionally, a lower limit value of the weight of each tank has a sufficient margin for fear that an air bubble may mix in. Further, there is a possibility such that a detected value of a weight sensor indicates a value smaller than an actual weight, since a liquid level shakes by the oscillation of a device or the like. If the detected value of the weight sensor indicates a state that the remaining amount falls short once, a safeguard is used so that a tank has not been used unless a coloring sensitive matter is newly filled in the tank. Thus, the amount of the coloring sensitive matter, which is actually left in a bottle assumed to be short on the remaining amounts, becomes relatively large, so that great deal of the coloring sensitive matter has been uselessly thrown aside. For example, 300 to 500 cc of the coloring sensitive matter per bottle was uselessly thrown aside. Sometimes, the coloring sensitive matter more than 1 kg was uselessly thrown aside. In the case of a general base of a color filter, it is possible to color about 300 to 500 sheets with a coloring sensitive matter of 1 kg. Further, according to circumstances, it is possible to color more than 1,000 sheets with a coloring sensitive matter of 1 kg. Therefore, its improvement has been strongly desired.